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Saturday, 31 October

JEE Main 2022 · ChemistryNumerical answerNumerical valueEasyCalculation

JEE Main 25 June 2022, Shift 1, Chemistry Q87

Question 87 of 90 in this shift, Chemistry question 27 of 30, Section B.

In a cell, the following reactions take place Fe2+→Fe3++e−\mathrm{Fe^{2+}} \rightarrow \mathrm{Fe^{3+}} + \mathrm{e^-} EFe3+/Fe2+∘=0.77 V\mathrm{E^\circ_{Fe^{3+}/Fe^{2+}}} = 0.77\ \mathrm{V} 2I−→I2+2e−2\mathrm{I^-} \rightarrow \mathrm{I_2} + 2\mathrm{e^-} EI2/I−∘=0.54 V\mathrm{E^\circ_{I_2/I^-}} = 0.54\ \mathrm{V} The standard electrode potential for the spontaneous reaction in the cell is x×10−2x \times 10^{-2} V 298 K. The value of xx is __________. (Nearest Integer)

Official answer

23

NTA final key.

Same idea in other shifts

Asked 13× in all
  1. 2 Apr 2026, Shift 1 · Q57An electrochemical cell is constructed using half cells in the direction of spontaneous change…MediumSingle correct
  2. 3 Apr 2025, Shift 2 · Q56The standard cell potential (Ecell⊖\mathrm{E^{\ominus}_{cell}}) of a fuel cell based on the oxidation of methanol in air that has been used to…MediumSingle correct
  3. 5 Apr 2024, Shift 2 · Q64For the electro chemical cell M∣M2+∣∣X∣X2−\mathrm{M|M^{2+}||X|X^{2-}} If E(M2+/M)0=0.46 V\mathrm{E^0_{(M^{2+}/M)}} = 0.46\ \mathrm{V} and…MediumSingle correct
  4. 9 Apr 2024, Shift 1 · Q85The standard reduction potentials at 298 K for the following half cells are given below :…MediumNumerical value
  5. 30 Jan 2024, Shift 2 · Q65Reduction potential of ions are given below: ClO4−\mathrm{ClO_4^-} E∘=1.19 VE^\circ = 1.19\ V; IO4−\mathrm{IO_4^-} E∘=1.65 VE^\circ = 1.65\ V;…EasySingle correct
  6. 6 Apr 2023, Shift 2 · Q86The standard reduction potentials at 298 K for the following half cells are given below:…MediumNumerical value
  7. 11 Apr 2023, Shift 2 · Q86The number of correct statements from the following is _______ A. Ecell\mathrm{E_{cell}} is an intensive parameter B. A negative…MediumNumerical value
  8. 28 Jul 2022, Shift 1 · Q70Which of the following has least tendency to liberate H2\mathrm{H_2} from mineral acids ?EasySingle correct

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.